Announcement: Avalonia DataGrid is Moving to a New Home

[MikeCodesDotNET]

We're making a small yet important change regarding the Avalonia DataGrid control.

This control, initially ported by a community member from Silverlight, has served us for quite some time. However, as many of you have noticed, it has remained largely unmaintained since its addition and inherited significant architectural flaws from the original Silverlight implementation.

After careful consideration, we've decided to move the DataGrid control out of the main Avalonia repository, back into its original dedicated repository. This move allows us to clearly signal our focus to maintaining and evolving the components that we believe best serve the community's needs.

What does this mean practically?

Very little changes for you:

• The DataGrid control will remain available on NuGet exactly as it is today.
• We will continue providing bug fixes, particularly for critical issues, ensuring stability for those who rely on it.
• For our commercial support customers, rest assured, this move does not affect the support you receive or commitments you've come to expect from us.

However, moving forward:

• We will not accept any new feature enhancements or significant changes to the existing DataGrid implementation.
• We actively encourage community members who wish to expand or significantly alter its functionality to fork the repository and innovate freely.

Recommended Alternative

For new projects or those looking for something more flexible, we strongly suggest exploring the TreeDataGrid control. This newer control was created specifically for Avalonia and provides a more robust, maintainable, and feature-rich experience for most scenarios.

This decision is part of our broader commitment to clarity in our control strategy. Our aim is always to ensure that Avalonia remains both powerful and user-friendly, and we believe this step brings us closer to that goal.

Thank you all for your understanding, continued support, and incredible contributions to Avalonia.

Cheers,
Mike

[robloo]

Also see: #16235

[IvanJosipovic]

The TreeDataGrid still considered "early beta" based on the readme. Is this sill the case?

Does a feature comparison exist between the two components?

[maxkatz6]

Updated that readme remark, as it's outdated at this point.
Typically, TreeDataGrid is more stable and performant, comparing to DataGrid. Especially in AOT/trimming scenarios.

Does a feature comparison exist between the two components?

There is no specific table. But both contain unique features that are missing from the another.

DataGrid-only features:

• Columns defined in XAML (TreeDataGrid columns has to be defined in C#)
• Grouping (TreeDataGrid can emulate it via tree hierarchy)
• Limited accessibility (TreeDataGrid has a PR for the same level of support)
• Column freezing

TreeDataGrid-only features:

• Tree structure
• Extended selection model, single-cell selection support
• AOT compatibility without reflection, including sorting (requires hacks for DataGrid), and overall better performance

Please visit TreeDataGrid docs for more details: https://github.com/AvaloniaUI/Avalonia.Controls.TreeDataGrid/tree/master/docs

[robloo]

Can you clarify the messaging around TreeDataGrid usage at this point in time? I understand these types of things are always subject to change.

1. A while ago it was going end of life. Long term plan is for it to continue under a paid license.
2. Then it was decided to keep it for around a year in the current form.
3. Now it seems the DataGrid is out instead (this has been discussed for years so understandable)
4. Now the direction is back to using TreeDataGrid.

My current understanding is DataGrid is being soft deprecated with this move and in some time will be archived. Hopefully forks pick it up as you said. TreeDataGrid is the replacement and it will eventually turn into a paid control with Avalonia Accelerate.

I imagine 3rd party libraries will come with DataGrid controls too eventually.

As an aside: I want to say the 2nd biggest reason people didn't adopt WPF back in the day was a lack of 1st party DataGrid. 1st being complexity and barrier to entry for devs used to WinForms. (My subjective judgement of course)

[MikeCodesDotNET]

Let me provide some clarity on our current position regarding DataGrid and TreeDataGrid:

Firstly, there are no plans to archive the existing DataGrid. Moving it back to its original repository is purely a signal that we don't anticipate adding new features or undertaking significant updates going forward. It will remain available as it is today for those who prefer or rely on it.

Regarding the TreeDataGrid (TDG), I want to assure you that it will always remain open-source. However, with Avalonia Accelerate, we're introducing a new, enhanced, paid version of the TreeDataGrid. This premium version will incorporate parts of the existing OSS codebase but will offer substantial improvements and additional capabilities.

The current OSS version of TDG will continue to receive bug fixes for our existing paying customers. If the wider community wishes to drive further enhancements, we will actively encourage forks and community-driven efforts.

We fully recognise that having a performant, flexible, first-party DataGrid control is vital to many developers evaluating UI frameworks. With these adjustments, our aim is not to reduce options but rather to expand them. Users can continue to use either the OSS DataGrid and the existing TDG exactly as they do today, while also gaining the option of a significantly enhanced TDG through Avalonia Accelerate.

I hope this helps clarify our direction. I appreciate the conversation around TreeDataGrid hasn't been the clearest.

[robloo]

Great! Thanks for the latest info: it certainly clarifies where we stand.

Personally, I'm looking forward to the enhanced version of TreeDataGrid with Avalonia Accelerate.

---

Final little note -- no need to take the time to respond. It's just something to consider in your internal discussions if it comes up.

I've been thinking about where the ecosystem stands for a while with table view controls I realize we really need two controls. WPF had ListView with GridView that could be used to quickly throw up a table of values. Super lightweight for apps to use. This was in addition to the full DataGrid. Due to different needs it's likely both a lightweight (TableView I'll call it) and heavyweight TreeDataGrid are needed. WinUI is also evolving this way in the community toolkit.

[almightyju]

We will not accept any new feature enhancements or significant changes to the existing DataGrid implementation.

This is disappointing, I've had some pull requests open for a while that adds support for users adding and deleting rows. Personally I find it a bit narrow minded to not accept any new features that bring it in line with WPF, I can understand the Avalonia team not developing new features, but not accepting community features makes me sad.

Guess I'll have to stick to maintaining my fork still 😢

[MikeCodesDotNET]

We always appreciate a PR, but ultimately, we have to consider the long-term impact of what we merge.

The original DataGrid contribution came from someone who didn't maintain it, leaving us with an architecturally challenging component to support, for both our OSS users and our commercial customers.

That’s why we make decisions like this, not out of narrow-mindedness, but to ensure Avalonia remains maintainable and scalable for everyone.

[almightyju]

I completely understand the lack of manpower meaning the data grid is essentially being put into maintenance mode.

I think it's reasonable to push the maintenance of the features onto contributors, or perhaps have a branch for community added features which you take no responsibility for other than accepting changes.

[robloo]

@almightyju Also keep in mind the DataGrid in Avalonia today is from the inferior Silverlight version of the control.

There was no choice at the time since WPF wasn't open source. Now however it would be better to port the WPF DataGrid and just use that. It's a much better foundation to start on even with its issues.

Nobody has time for this so far, but someday I think someone will port WPF's DataGrid and when that happens this old version is instantly discarded by almost everyone.

[almightyju]

@robloo I get that it came from Silverlight and is essentially tech debt.

I'm not criticising the decision of the Avalonia team to put the control in maintenance mode. I'm criticising the mindset of "we don't want to maintain new features so we aren't going to accept any" because it's just going to lead to a bunch of forks appearing where people add the feature they want. If we do see lots of features in forks perhaps one of them will become the go-to, we will see.

someday I think someone will port WPF's DataGrid

I can't see that happening any time soon, but if that is the long term plan then there isn't an issue, this announcement just reads to me as "we don't like the datagrid, it's a massive time sink, so we're not going to improve upon it anymore or let anyone else improve it"

[grokys]

a bunch of forks appearing where people add the feature they want. If we do see lots of features in forks perhaps one of them will become the go-to,

That would be a fantastic outcome IMO and a promising sign of health in the Avalonia ecosystem. I know that the .NET space is used to a single company being the blessed source for all libraries, but that's really not common in the wider OSS world. It's essentially only the case in the .NET space because MS is one of the most wealthy corporations on the planet. AvaloniaUI is a bit smaller than MS. I don't see people expecting Mozilla to maintain every useful crate in the Rust world.